Rotary piston machine



June 22, 1965 o. GRIGAR ROTARY PISTON mcnmm Filed Sept. 16, 1963 m .I. a n i un Ti aw INVENTOR ATTORNEYS United States Patent 3,190,228 ROTARY PISTON MACHINE Otto Grigar, Landtestrasse 47, Bienne, Switzerland Fiied Sept. 16, 1963, Ser. No. 309,142 Claims priority, application Switzerland, Sept. 21, 1962, 11,173/ 62 3 Claims. (Cl. 103-130) This invention relates to a rotary piston machine, comprising at least one pair of rotary pistons having each a cylindrical surface and adapted for rotary displacement each in a cylinder of a diameter exceeding the diameter of the piston, a guideway interconnecting the said pair of cylinders and extending in a direction substantially comprising the axes of the cylinders, separating-gate means displaceable along said guideway in a direction substantially radially to the cylinder surfaces and rotary piston surfaces respectively, means for displacing said rotary pistons along the cylinder surfaces with one mantle line of each rotary piston contacting one mantle line of the cylinder surface for any position of the rotary piston, means for urging said separating gate means against the surfaces of the rotary pistons, said separating-gate means being radially displaced by the rotary pistons, said means for displacing said rotary pistons along the cylinder surfaces being so synchronized that the said separating-gate means are maintained in engagement with both rotary pistons by synchronized displacements in the same direction and by equal amounts.

In such a machine which may be a combustion motor, a compressor or a pump, the separating-gate means or sealing-slider means are positively controlled by the rotary pistons and no spring means are required for displacing the separating-gate means. Individual separating gates may be associated with each rotary piston, such separating gates being urged against the piston surfaces by pressure medium admitted between the separating gates from the high pressure chamber of at least one of the cylinders, or a pressure spring being disposed between the separating gates or sliders for urging them against the piston surfaces.

One embodiment of the invention is shown, by Way of example in the attached drawing, wherein FIG. 1 is a section of the machine along line II in FIG. 2,

FIG. 2 is a section of the machine along line [Ill in FIG. 1 and FIG. 3 is a top View of a pair of sealing pads.

The rotary pistons 1 and 2 of the machine are rotatably mounted on eccentrics 3 and 4 fixed on shafts 5 and 6. The pistons 1 and 2 are accommodated in cylinders 7 and 8 having a diameter exceeding the piston diameter, the cylinders being formed in a casing 9. Upon rotation of the shafts 5 and 6 the rotary pistons 1 and 2 will roll along the cylinder surfaces, whereby one mantle line of each piston contacts one mantle line of the cylinder surface for any angular position of the piston and of the shaft respectively. In a bore or guideway 10 extending in a direction comprising the axes of the cylinders 7 and 8 and of shafts 5 and 6 respectively, a pair of individual separating gates or sealing sliders 11 and Rare slidably inserted. The separating gate 12 has two sealing rings 13. The separating gate 11 has a cylindrical projection 14 engaging a bore 15 of the gate 12. The bore 15 communicates with a cylndrical fluid chamber 16 interconnected with the cylinder 8 at the left side of gate 12 by means of a canal 17 comprising a return stop valve 18.

Pairs of individual sealing pads 19 and 20 are pivoted and axially displaceable in cylindrical grooves 21 of gates The chambers 23 are connected with the one chamber of the cylinders 7 and 8 respectively by canals 24. As most clearly shown in FIG. 3, the sealing pads 19 and 20 have notches 28 and grooves 29 respectively engaging into each other and extending throughout the radial width of the pads and forming a labyrinth sealing preventing fluid ex change between the sides of the sealing pads through the joint between the sealing pads.

Gear means, not shown in the drawing, are provided between shafts 5 and 6 whereby such shafts are rigidly coupled and are synchronously driven at the same speed and in rigid phase relation in opposite direction.

As shown in FIG. 1, inlet canals 25 communicate with the right side of cylinders 7 ands While outlet canals 26 including non-return valves 27 communicate with the left side of the cylinders '7 and 8.

In operation the shafts 5 and 6 with eccentrics 3 and 4 are driven at the same speed in opposite direction in such a phase relation that both pistons 1 and 2 will reach their upper end position at the same time. Consequently, the pistons will also reach their lower end position at the same .time after one half revolution of the shafts 5 and 6. Under these circumstances the sealing pads 19, 20 and the separating gates 11 and 12 respectively are displacedsynchronously according to a sinus oscillation. The separating gates are displaced from their upper end position shown in FIG. 1 by the upper piston 1 during the next half revolution of the pistons and will then be moved upwardly by the lower piston 2. Assuming that the piston surfaces are strictly cylindrical, and that their displacement is strictly synchronized, no relative displacement of gates 11 and12 will occur and such gates will be moved in strict synchronism. Due to the rotation of pistons 1 and 2 the medium will be sucked in through inlet canals 25 into the suction chambers formed at the right side of pistons 1 and 2 and the medium will then be compressed in the compression chambers formed at the left side of the pistons, from where the compressed medium is discharged through outlet canals 26. Since the fluid chambers 16 and 23 communicate with the pressure chambers of cylinders 7 and 8, compressed medium is admitted to such fluidchambers, whereby the pressure is maintained at a minimum level in chamber 16 due to the non-return valve 18. By this pressure medium acting in chamber 16 the gates 11 and 12 and sealing pads 19 and 20 respectively are pressed against the piston surfaces. By the compressed medium admitted to the fluid chambers 23, the end surfaces of the sealing pads 19 and 20 are pressed against the end surfaces of the cylinders 7 and 8 whereby the sealing action is improved; The pressure of the sealing pads 19 and 20 against the piston surfaces and against the end surfaces of the cylinders depends on the working pressure in the cylinders.

While the machine as illustrated in the drawing and as described above preferably operates as a compressor for gases or a pressure pump for liquids, the machine may be used as a fluid motor or as an explosion motor with rela tively slight modifications. When the non-return valves .27 are removed, the machine will operate as a fluid motor,

' also be rotated in the same direction. More than one pair of cylinders and rotary pistons may be provided whereby the rotating directions and phases of the rotary displacement may be chosen for compensating mass forces.

;In a double-stage pump or compressor the compression Patented June 22, 19 5.

chamber of the one cylinder may be connected to the 811C:

tionchamber of the other cylinder, whereby the higher:

pressure cylinder and piston of a compressor may have smaller axial dimensions than the cylinder and piston of the first stage; V ,7 In compressors or'vacuum pumps the sealing pads 19 period. Pressure springs may be provided for obtaining an initial sealing pressure, while the pressure during normal operation is produced and depends on the pressure of the compressed medium admitted to the chambers 16 and- 23. However, such pressure chambers may completely be omitted and replaced by pressure springs particularly in vacuum pumps Where -no overpressure is. usually prothe diameter of the piston,.aguideway extending inta dire-etion substantially radially of the'cylinder,separating-gate and 20 may not properly, engage the piston andcylinder surface due to the lack of pressure during the starting up means displaceable along said guidewayin a direction substantially radial to the cylinder surface and rotary piston surface respectively, means for displacing said rotary pis ton along the, cylinder surface with one mantle line of the rotary pistoncontacting-one mantle line of the cylinder surface for any position of the rotary pistonpmeans for urging said separating gate means against thesurface' of the rotary piston, a pair of sealing pads pivotably mounted in said separating-gate means round an axis parallel to the V between suchsealing pads. 2. A rotary piston machine according to claim: 1, com

. prising piston and cylinder means between each .pair of a cylinder axis and having 5 end surfaces of the cylinders, and labyrinth sealingmeans between such sealing pads'preventing circumferentialflow sealing pads, a, suction chamber and a pressure chambjerin said cylinder at oppositesides of the separating gate, said cylinder means communicating with said pressure chamber.

V 3. Arotary pistonmachine according to claim2, where- V in the one sealing pad ofeach pair of sealing'pads has a cylindrical projectionengaging into a cylindrical bore of the other, sealing pad of the pair of sealing pads, said cylindrical projection and bore forming the said pistonand cylinder means respectively. k 7

References Cited by the Examiner:

UNITED STATES PATENTS I 936,932 10/09 Neumann ,230f-149 1,582,960 :5/26 Berrenberg 230-149 j 1,582,961 5/26 Berrenberg 230 -149 7/55 Huber 103 13o FOREIGN PATENTS 573,247 *3/24 France.

1,877 11/77 Germany. 318,688 2/20' Germany.

KARL J. ALBRECHT, Primary Examiner.- WILBUR J. GOODLIN, Examiner.

V cylindrical sealing surfaces en. gagingthe piston surface, pressure means between such sealing pads'axially urging such sealing pads against the- 

1. A ROTARY PISTON MACHINE, COMPRISING AT LEAST ONE ROTARY PISTON HAVING A CYLINDRICAL SURFACE AND ADAPTED FOR ROTARY DISPLACEMENT IN A CYLINDER OF A DIAMETER EXCEEDING THE DIAMETER OF THE PISTON, A GUIDEWAY EXTENDING IN A DIRECTION SUBSTANTIALLY RADIALLY OF THE CYLINDER, SEPARATING-GATE MEANS DISPLACEABLE ALONG SAID GUIDEWAY IN A DIRECTION SUBSTANTIALLY RADIAL TO THE CYLINDER SURFACE AND ROTARY PISTON SURFACE RESPECTIVELY, MEANS FOR DISPLACING SAID ROTARY PISTON ALONG THE CYLINDER SURFACE WITH ONE MANTLE LINE OF THE ROTARY PISTON CONTACTING ONE MANTLE LINE OF THE CYLINDER SURFACE FOR ANY POSITION OF THE ROTARY PISTON, MEANS FOR URGING SAID SEPARATING GATE MEANS AGAINST THE SURFACE OF THE ROTARY PISTON, A PAIR OF SEALING PADS PIVOTALLY MOUNTED IN SAID SEPARATING-GATE MEANS ROUND AN AXIS PARALLEL TO THE CYLINDER AXIS AND HAVING CYLINDRICAL SEALING SURFACES ENGAGING THE PISTON SURFACE, PRESSURE MEANS BETWEEN SUCH SEALING PADS AXIALLY URGING SUCH SEALING PADS AGAINST THE END SURFACES OF THE CYLINDERS, AND LABYRINTH SEALING MEANS BETWEEN SUCH SEALING PADS PREVENTING CIRCUMFERENTIAL FLOW BETWEEN SUCH SEALING PADS. 